Diamond bits



Dec. 20, 1955 Filed June 28, 1952 E. G. BOICE DIAMOND BITS 2 Sheets-Sheet 1 E/l//n 6. Bo/ce 1N VEN TOR.

ATTORNEY@ Dec. 20, 1955 E. G. BolcE 2,727,729

' DIAMOND BITS Filed June 28, 1952 2 Sheets-Sheet 2 E/V/n 6. 15o/ce INVENTOR.

ma ZM ATTOR/VE YJ 2,727,729 DIAMOND BITS Elvin G. Boice, Houston, Tex., assigner to Reed Roller Bit Company, Houston, Tex., a corporation of Texas Application June 2s, 1952, serial No.296,zz4 4 claims. (ci. iss-.72)

This invention relates to new and useful improvements in diamond bits for the drilling of oil wells andtthe` like. v

4 As is well known, the lineal `or annularspeed of diamonds is c ritical in drilling bore holes. There is an opti mum 'diamond speed, for any given formation, at which the diamonds are extremely efficient at removing the formation. If this optimum annular speed is greatly exceeded or reduced the cutting efficiency of the diamonds is greatly impaired and in many instances the diamonds are lost or destroyed. If a diamond bit is designed to' cut the entirev bore hole diameter, the diamonds at or near the center of the bore hole have little or no linear speed and; consequently, penetration is very slow and 4the paired. l p p In the past there have been attempts to solve this probbit life `severely im- Ylem by placing the diamonds on an annularring whereby thediamond speed may be maintained at or near the optimum. In these devices the central portion of the bore hole remains uncut thereby necessitating a core barrel to receive this uncut portion which is known as the core. The core barrel usually is'on the order of 30 to 40 `feet long. When the barrel has received a core equal to its core length, drilling operations are suspended; the Vcore broken off; and the entire drill string is removed so that the core may be removed from the core barrel after which the diamond core bit and core barrel are again lowered into the bore hole. This operation'must be repeated for every 30 or 40 feet of bore hole drilled notwithstanding the fact that the diamond core bit itself may have a useful life of hundreds of feet or more.'

It is therefore an object of this invention to provide a diamond bit `wherein the full diameter of the bore hole is diamond cut, thereby eliminating the necessity for removing the bit as in the case of the usual diamond coring bits. t

An important object of this invention isto provide a diamond bit having an annular cutting surface and a reciprocating center cutter therewith, `whereby the full diameter ofthe bore hole is cut by the annular cutting surface and the center cutter.

Another object of this invention is to provide a valveless,A iiuid operated, reciprocating engine.

The construction designed to carry out the invention will be hereinafter described together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown, and wherein:

Figure 1 is a longitudinal sectional view of the com plete diamond bit of this invention as taken on line 1-1 of Figure 4.

Figure 2 is a view similar to Figure 1, and illustrates the reversing mechanism operation.

the bit will not drill or the bit rate of Figure 3 is a vertical sectional view taken on line 3 3 of Figure 2. 'i

Figure'4 is a bottom view of the diamond bit of this invention.

Figure 5 is ahorizontal 5-5 of Figure 3.

In the drawings,` the letter A` designates generally the diamond bit of this invention. The diamond bit A sectional view taken on line ,has abit body which includes a sleeve 10 and a bit head 11. The upper end of the sleeve 10 is welded or otherwise aixed to a connecting member such as the tool joint pin 12 for connection withthe usual drill string extending to the surface of the well, whereby rotation is imparted to the diamond bit A through the drill string and also drilling fluid is carried through the bore thereof for drilling operations. The bit head 11 has an annular cutting surface 14 which extends alongthe bottomv and sides thereof, leaving a central or axial bore 15 therethrough. The bit head 11 also has a transverse bore 16 therein somewhat above the bottom of the bit head, and such transverse or lateral bore 16v has mounted therein, a Areciprocal central cutter 17 which has reciprocatory motion imparted thereto by a valveless, uid operated reciprocating engine designated generally as 18,V and which will be described in detail hereinafter. With the diamond bit of this invention, the full diameter of the bore hole is cut, since the hard wearing surfaces 14 cut the annular groove and leave an uncut central portion which extends into the axial bore 15 for a short distance, whereby the reciprocating cutter 17 may cut away such uncut central portion.

`Referring now to Figures l and 3 particularly, therein can be seen the details of the fluid operating reciprocating engine 18 of this invention. Such engine 18 includes paddles 20 which serve as actuating members for the engine 18. These paddles 20 are preferably of a tapered cross section with an upper pointed end 20a; Holes V20b may be provided in the paddles 20 in order to reduce the weight thereof. The lower end of the paddle 20 is connected to a link or lever 22 by means of a pin 23 to providea pivotalconnection therebetween. As can be seen, the pivot pin 23 extends through a clevis portion 20c of the paddle 20, such clevis portion 20c having a flat' upper section 20d which coacts with oppositely inclined surfaces 22a and 22b on the upper end of the link 22, as will be explained in detail hereinafter. Thelink 22 is pivoted to the bit head 11 by a pivot pin 25, which has the ends thereof extending into-l pin slots 26 in the bit head 11. The pin 25 is restrained from lateral movement by the lower end of the sleeve 10 which has a inner bore 10a of enlarged diameter as compared to the upper bore 10b of the sleeve 10.

The `lower end of the link or lever 22 is in the form of a clevis 27 which has open notches 28 at the lower end of each leg of the clevis 27. These open notches 28 fit over lugs 29 which are mounted on a yoke 30 fitting into a radial groove 31 in the reciprocating member 17. Thus, pivotal movement of the link 22 imparts reciprocatory movement tothe cutter 17 and such pivotal movement of the lever 22 is obtained by reason of Huid impinging upon the exposed surface of the paddle 20 and by coaction of the paddle 20 with `stop members such as the rods 33 threaded into the sleeve 10 and extending into the bore 10b on diametrically opposite sides thereof.

The reciprocating cutter 17 has hard wearing inserts 17a disposed on its outer surface, which inserts 17a are substantially of the same character as the inserts 14a on the annular cutting surface 14. Although these inserts are preferably diamonds, and are referred to herein as such, it will be appreciated that other hard wearing materials could be utilized in the place thereof; for example,

the yoke 30 and pin 29 connection.

tungsten carbide inserts could be used instead of diamonds. Mud or slush is supplied to the diamond bit A of this invention from the surface of the well through the drill string (not shown) so that it is received into the bore b of sleeve 10 forming part of the bit body and is then conveyed to the annular cutting surface 14 and the reciprocating cutter 17 through longitudinal slush passages 35 and through the axial bore 1S of the bithead 11. It will be observed that the opposite ends of the cutter 17 are of smooth cylindrical construction whereby these ends 17b can readily reciprocate within the transverse or lateral bore 16 of the bit head 11. The uid or mud which is supplied for the drilling serves to lubricate the movement of the reciprocating member 17. Additionally, as best seen in Figure 3 an axial opening 17c in communication with radial openings 17d are preferably provided within the cutter 17 to reduce a braking action by any uid which may be present in the lateral bore 16 during the movement of the reciprocating cutter 17.

In the operation of the bit of this invention, the bit A is lowered into'the well on a drill string (not shown) which is connected to the tool joint section 12 and upon reaching the bottom of the bore hole, the drill string and bit A are rotated and mud or slush is supplied through the drill string, as in the usual drilling operations. The

drilling uid initially, upon entering the sleeve bore 10b contacts the upper or exposed surface of the paddle 20,

assuming it to be in the full line position shown in Figure 1. The fluid action on 'the paddle 20 imparts a lateral movement to the paddle 20, moving it to the dotted line position shown in Figure l. The paddle 2i) is prevented from pivoting beyond the position shown in Figure l by reason of the contact of the inclined surface 22b with the at bottom surface' 20d. As will be appreciated when the paddle moves to the dotted line position shown in Figure 1 the link or lever 22 is likewise moved laterally and due to the pivot 25 a reciprocatory movement is imparted to the cutter 17 through Upon the paddle 20 reaching the dotted line position as shown in Figure 1, the uid continues to act thereon but the stop rod 33 prevents the upper end of the paddle 20 from continuing its lateral movement. Therefore, the lower end of the paddle 20 is moved laterally while the upper end thereof is held by the rod 33, which reversing rod 33 serves to move the paddle 20 to the full line position shown in Figure 2. It can therefore be seen that a full stroke of the uid operated motor 18 involves movement from the full line position shown in Figure l to the full line position shown in Figure 2. When the paddle 20 reaches the full line position of Figure 2 the reverse movement of' the paddle 20 and its connected parts is obtained by action of the fluid now impinging upon the other surface of the paddle 20 from that which was originally contacted in Figure 1. Movement of the reciprocating cutter 17 can be continued, as` will be evident,so long as fluid is supplied to contact the paddle 20, and such action is maintained continuously without the necessity for valves or other similar structure.

After the uid which enters the bore 10b has reacted against the paddle 20 it passes downwardly to provide lubrication for the reciprocating cutter 17 and to perform its usual drilling duid functions in connection with the abrading section ofthe cutter 17 and the annular cutter surface 14 of the drill bit head 11.

The foregoing disclosure and description of the invention is illustrative and explanatory thereof and various changes in the size, shape and materials, as well as in the details of the illustrated construction may be made, within the scope of the appended claims, without departing from the spirit of the invention.

What is claimed is: v f

l. A diamond bit for cutting the full diameter of a bore hole, comprising a bit body having a central axial bore therein, an annular cutting surface adapted to cut an annular path in the bottom of the bore hole leaving a central uncut portion, a reciprocating central cutter in said axial bore to cut said central uncut portion of the bore hole, whereby the full bore hole diameter is cut, said bit body including a transverse bore, said center cutter being disposed in said transverse bore, and a fluidoperated drive means connected to said center cutter to reciprocate said cutter in said transverse bore.

2. As a subcombination in a diamond bit, a valveless, timid-operated means adapted to be disposed within a 10ngitudinal bore, a cutter mounted within a transverse bore for reciprocatory movement therein, said Huid-operated means being attached to said cutter for reciprocating the same, a sleeve defining said bore, an actuating member forming part of said fluid-operated means and mounted in said sleeve and adapted to move substantially laterally of the bore upon impact thereon of uid passing through said longitudinal bore, a transmitting means connected to said actuating member for transmitting the substantially lateral movement of the actuating member to said cutter, and reversing means in said sleeve diametrically opposed'to each other and extending partially into said longitudinal bore and adapted to touch said actuating member to cause the latter to move in opposite lateral directions to thereby provide a recprocatory motion to said actuating member.

3. The subcombination as defined in claim 2, said actuating member comprising a paddle which is transversely pivoted to the end most remote from said cutter of said transmitting means.

4. A diamond bity for cutting the full diameter of a bore hole, comprising a bit body having a central axial bore therein and also a transverse bore therein, an annular cutting surface composed of diamond inserts on the lower end of said bit body adapted to cut an annular path in the bottomof the bore hole leaving a central uncut portion, a reciprocating center cutter having diamond inserts on the surface thereof in said transverse bore to cut said central uncut portion of the bore hole, whereby the full bore hole -dameter is cut, and a valveless, fluid-operated means operatively connected to said center cutter to reciprocate said center cutter in said transverse bore transversely of the well bore.

References Cited in the tile of this patent UNITED STATES PATENTS 576,931 Wolf Feb. 9, 1897 1,457,181 Mable May 29, 1923 2,497,144 Stone Feb. 14, 1950 2,619,325 Arutunot May 25, 1952 2,626,780 Ortloi Jan. 27, 1953 2,667,334 Ort-lofi Jan. 26, 1954 FOREIGN PATENTS 66,420 Norway July 45, 1943 

